Electric clock



June 29, 1937. J BERT] 2,085,071

ELECTRIC CLOCK Filed May 11, 1935 2 Sheets-Sheet 1 INVENTOR dbseph Berti J. BERT] ELECTRIC CLOCK June 29, 1937..

Filed May 11, 1935 2 Sheets-Sheet 2 INVENTOR cfash Berta ORNEY Patented June 29, 1937 UNITED STATES PAT QFFICE ney- Walker Co. Inc.

, New York, N. Y., a corporation of New York Application May 11, 1935, Serial No. 21,003

9 Claims.

This invention relates particularly, though not exclusively, to electric clocks for automobiles. In addition to being accurate and reliable, these clocks should not be affected by or in any i .5 way afiect or impair the operation of the car.

Under certain conditions, the contacts of such clocks may stick togetherand produce a virtual short circuit, which will burn out the clock or rundown the battery, or both. At times, particu- -110 larly when a car is in storage, the battery may be so low that it will not operate the clock magnet and will then leave the contacts engaged permitting the battery to run down completely.

Special objects of the present invention are to I .15 overcome and eliminate the faults mentioned and to provide a clock structure which will be both self-protective and a protection against such possible drains on the car battery.

Other objects of the invention are to enable such improvements being incorporated in present day Watch or clock movements, at low cost and to provide the required parts or structure in simple practical form.

The foregoing and other desirable objects are attained by the novel features of construction, combinations and relations of parts hereinafter described, illustrated in the accompanying drawings and broadly covered in the claims.

' In the drawings several simple commercial embodiments of the invention are shown, but as such illustration is primarily by way of disclosure it will be understood that changes and modifications in the form of the device may be made, all within the true spirit and broad scope of the invention.

Fig. 1 is a rear View of one of the clocks with the clock casing broken away to show interior parts and appearing partly in section. V Fig. 2 is a broken part sectional view as on line 2-2 of Fig. l and on a larger scale illustrating details of the push button thermostatic switch.

Fig. 3 is a broken sectional detail of one form of insulating support for mounting the move- 1 I ment in the clock case, taken as on a line 3-3 of Fig. 1.

Fig. 4 is a view similar to Fig. 1, illustrating a somewhat simplified form of the invention.

Fig. 5 is an enlarged sectional detail of the latter as on line 5-5 of Fig. 4.

; i 5.5 which the watch or clock movement generally indicated at 1, is electrically connected with the metallic case 8, in which it is mounted. This is effected by the posts or pillars 9, projecting from the back plate of the movement being secured to the back of the case by screws Hi.

When it is required that the movement be insulated from the case, this may be accomplished as indicated in Fig. 3, by the interposition of insulating bushings l I, between the case and the ends of the movement posts Q.

Mounted on the case are shown two circuit terminals I2, [3, insulated from each other and from the case by suitable insulating bushings, washers, or the like 84.

In the particular form of clock movement shown, the energy for driving the clock train is supplied by tension spring l5, connected with one end of a lever l6 geared to the clock train at H. This spring impelled lever has an oppositely extending arm l8, carrying a contact I 9, engageable with a contact 20, on the inner end of a magnetic core element 2|, operating in a solenoid 22. This core slides in the metallic center tube 23, of the solenoid and one end of the winding is electrically connected therewith as indicated at 24. The sliding engagement of the core in the tube thus brings the core or armature into the circuit of the magnet. Positive connection between the tube and core is provided in the illustration, apart from and in addition to such sliding contact, through the spring 50, interposed between the outer ends of the core and tube.

The other end of the magnet winding is shown extending at 25, beneath the nut 26, on the screw 21, which latter holds the insulating magnet support 28 and insulating bushing 29, to the lug 30, on the back movement plate.

A spring strip 3|, caught between the head of screw 21, and insulating washer 32, completes the insulated side of the magnet circuit to the binding post or terminal l2. The other, or grounded side of the circuit is completed through the main spring lever, back movement plate and posts 9, to the case. As will be clear from Fig. 1, the spring strip 3l forms a yielding electrical connection between the magnet and the insulated circuit terminal on the clock case enabling relative separation of said clock case and spring winding magnet.

In Fig. 2, a guide bushing 33, is shown riveted or otherwise suitably secured in the back wall of the case and slidingly operating in this bushing, there is shown a plunger 34, acted on by a retracting spring 35, engaged between the base of the bushing and the hollow button or cap 36,

fixed to the outer end of the plunger.

A flange 37, on the plunger at the inside of the case limits the outward retractive movement.

The inner end of the spring retracted plunger 34, carries a relatively sharp or abrupt shoulder 38, engageable by the flexing free end portion 39, of a thermostatic element 40, mounted on and carried by the inner end of the insulated terminal post l3.

With the terminal I3 connected with the opposite side of the line and with the inner end of the push button caught and held by the free end 39 of the thermostatic bar, it will be seen that upon engagement of the lever and core contacts I9, 20, circuit will be completed through the thermostatic switch described.

In case of extra heavy current flow or of continued flow which might injure the parts or run down the battery, the thermostatic element 40, will expand and shift out of holding engagement with the spring switch element, as in dotted lines, Fig. 1, releasing that element and interrupting the magnet circuit at this point;

The circuit interrupted by the thermostat may be closed again when desired, by simply pushing in on the button end 36, of the spring plunger, the crowned or inclined head 4|, at the inner end of the plunger then forcing its way past the flexible end of the thermostat bar and enabling the latter then to snap into holding relation beneath the shoulder 38.

In addition to operating as an automatic switch and as a manually clos'able switch, the thermostatic switch may be opened manually at any time, by simply pulling out on the button end of the switch plunger, so as to forcibly carry the holding shoulder 38, on the inner end of the same past the flexible free end of the thermostat bar.

The insulation or non-insulation of the several parts may depend on the particular manner of mounting the clock.

For instance, in. mirror clocks where the clock case is mounted directly in a glass mirror and hence is insulated from other parts of an automobile, no insulation is necessary or possibly desirable between the movement and clock case and consequently, the insulation illustrated in Fig. 3 may be entirely omitted. In such case, the insulated terminal I3, would have a wire connection with some grounded portion of the car.

Even in dash mounted clocks, a grounding connection may be run from the terminal I3, to some Well grounded portion of the vehicle or to a wire return to the battery. The two wire connections to the clock are considered desirable in the late model cars, where insulation is used at different points in the car body for sound insulating purposes.

Figs. 4 and 5, show how the push button mounting may be utilized for terminal purposes by forming the hub of the bushing 33, with a screw neck or base 42, receiving the terminal eyelet 43, for the positive battery wire 44, said terminal eyelet being secured by an overstanding nut 45, on said screw-threaded portion.

In this particular instance, the push button mounting is insulated from the clock case as by suitable insulating bushings and. washers at 46, being held in such relation as by a rivet head or other fastening 41, at the inner end of the same.

In this second form of the invention, the push button element is shown disposed in the insulated side of the circuit and further, as indicated in Fig. 4, the thermostatic element 40, is shown as substituted in place of the spring connecting strip 3| (Fig. 1), which leads the current to the magnet.

In this last described form of construction, the movement may be in direct electrical connection with the case and the case may or may not be provided with a grounding terminal, such as indicated at 48, depending upon whether the case in its particular location will be sufficiently grounded or will require a special grounding wire.

The thermostatic element may be heated by carrying current through the same as indicated in Figs. 1, 2 and 4, or it may be made as indicated in Fig.6, with a special heating winding 49. It is possible that other forms of thermostatic elements may be utilized, but the two forms illustrated are at present considered most suitable for the purpose.

Preferably, the thermostat will be sufiiciently sensitive as to heat fairly quickly with continued flow of current even with a partially run down battery, so as thus to automatically open the circuit at a time when the battery may be so low as to be unable to operate the spring energizing magnet. This is to make sure that by no chance will the clock drain the battery. In case of a mechanical break in the clock, or for example, dirt or grit stopping the clock with the contacts in engagement, the thermostat will then operate to cut the clock out of service and save it and the car battery from injury.

In addition to the advantages noted and apparent, the structure is such that it may readily be combined with present day watches and clocks at low cost and, in some instances, such as in a simplified form, Figs. 4 and 5, possibly at no additional expense over present costs.

While the invention is particularly well adapted to a form of clock movement such as here shown, it will be apparent that it may be combined with various other forms of electric clocks. The thermostatic switch mechanism may be mounted wholly on the case as in the first form of construction, or be partly on the case and partly combined with the spring winding motor as in the second construction (Figs. 4 and 5), or in some instances, the thermostatic switch mechanism may be carried entirely by the movement. Other variations are possible. The expressions employed herein have therefore been used in a descriptive rather than in a limiting sense and should be so construed, except possibly as limited meaning may be imposed by state of the prior art.

' What is claimed is:

1. In combination, a metallic clock case, a grounding element on said case, a thermostatic element mounted in insulated relation on said case and cooperable with said grounding element to form an electric switch, a .clock spring winding magnet in said clock case having a grounded side connected with the clock case and an insulated terminal on the clock case for the other side of said Winding magnet, said grounding element being in the form of a spring shifted member and the thermostatic element having a detent connection therewith to releasably restrain said spring shifted member.

2. In combination with a metallic clock case, a spring retracted push button mounted on and in electrical connection with said clock case, a thermostatic detent for releasably retaining said push button. against the tension of its retracting in insulated relation on said clock case and a clock spring winding magnet in said clock case in electrical connection with said thermostatic detent when the latter is in retaining engagement with said push button.

3. In combination with a metallic clock case, a spring retracted push button mounted on and in electrical connection with said clock case, a thermostatic detent for releasably retaining said push button against the tension of its retracting spring and a clock spring winding magnet in said clock case in electrical connection with said thermostatic detent when the latter is in retaining engagement with said push button, an insulated support for said thermostatic detent on said clock case, an insulated circuit terminal for said magnet on said clock case and a yielding electrical connection between said magnet and said insulated circuit terminal on the clock case for enabling relative separation of said clock case and clock spring winding magnet.

4. An electric clock, comprising a case, a spring retracted push button mounted on said case and having a holding shoulder, a thermostatic element mounted on said case in engagement with said holding shoulder and shiftable in the heating of the same free of said holding shoulder, an electric clock movement in said case in electrical connection with said thermostatic element, said case being of conducting material, said push button being in electrical connection with said case, the thermostatic element being insulated from the case and the movement being in electrical connection with the case.

5. An electric clock, comprising a case, a spring retracted push button mounted on said case and having a holding shoulder, a thermostatic element in engagement with said holding shoulder and shiftable in the heating of the same free of said holding shoulder, an electric clock movement in said case in electrical connection with said thermostatic element, said thermostatic element being mounted on said clock movement, said case being of conducting material and the push button being insulated from said case and having an external circuit connection.

6. In an electric clock, the combination of clock movement and case, a spring shifted member projecting from the case and forming a part of the electric clock circuit and a thermostatic element within the case also included in the clock circuit having holding engagement with said movable member and movable under temperature conditions to release said movable member to interrupt the clock circuit.

7. In an electric clock, the combination oi. relatively separable clock case and movement, a clock spring winding magnet mounted on said movement, a thermostatic bar also mounted on said movement and in the electrical circuit of said clock spring winding magnet, a movable switch element mounted on said clock case in position for cooperative engagement with said thermostatic bar on the clock movement, a spring for shifting said switch element in a circuit opening direction, said switch element being arbitrarily shiftable into and out of engagement with said thermostatic bar, independently of the condition of the latter and said thermostatic bar having a holding connection with the switch element in opposition to said circuit opening spring, whereby said switch element may be operated to open or close the clock spring winding magnet circuit and the clock case be separated from the movement, independently of the condition of the thermostatic bar and means for connecting said movable switch element in an external energizing circuit for said clock spring winding magnet.

8. In an electric clock, the combination of a clock movement and an enclosing case of conducting material, a clock spring winding magnet mounted on said movement, a spring shifted member mounted in insulated relation on said clock case, a thermostatic element within said clock case, in the electrical circuit of said clock spring winding magnet and having holding engagement with said spring shifted member and movable under temperature conditions to release said movable member and means for connecting said spring shifted member in an external energizing circuit for said clock spring winding magnet.

9. In an electric clock, the combination of a clock movement and an enclosing case, a clock spring winding magnet in said case, said case and movement structures being relatively separable, terminals mounted in relatively insulated relation on one of said two structures, a thermostatic switch within said case structure and including relatively insulated, engageable and separable switch elements, one connected with one of said relatively insulated terminals and the other connected with said clock spring winding magnet and make and break switch mechanism under control of said clock spring winding magnet for intermittently connecting said magnet with the other of said relatively insulated terminals.

JOSEPH BERTI. 

